Production of artificial silk by the stretch spinning process



Jan. 14, 1936. BAUREDEL r AL 2,027,895

PRODUCTION OF ARTIFICIAL SILK BY THE STRETCH SPINNING PROCESS Filed NOV. 12, 1923 .772ver2 fors Patented Jan. 14, 1936 PATENT OFFICE PRODUCTION OF ARTIFICIAL SILK BY THE STRETCH SPINNING PROCESS Gotthard Bauriedel and Ewald Knehe, Barmen, Germany, assignors to American Bemberg Corporation, New York, N. Y.

Application November 12, 1928, Serial No. 318,785 In Germany November 21, 1927 '1 Claims.

The invention relates to the production of artificial silk, for example copper oxide ammonia silk by the stretch spinning process. This process has been carried out previously by using the collecting device for the spun thread, for example, a reel or a bobbin, at the same time as the device for giving the required tension to the thread during the spinning process, that is to say, the collecting device was at the same time a drawing device. In consequence of this, the thread was laid upon the bobbin or reel employed under considerable tension, which rendered necessary, particularly in the case of reels, a relatively heavy construction, since a considerable mechanical stress is produced by the silk wound on the reel in many turns.

when winding on to bobbins, the washing of the silk in the bobbins was made difflcult owing to the numerous tight windings lying one on the other.

These disadvantages are avoided by the process according to the invention. According to this process, the thread is previously formed in a stretch spinning apparatus, is then subjected to a considerable stretching by a suitable drawing device, and. is conducted from the latter drawing device to the winding-on device under adjustable tension or without tension. This process not only avoids the disadvantages described, but has the advantage that the resistance of the thread can be considerably increased by the second stretching of the thread outside the spinning funnel.

Apparatus of various kinds may be used to carry out the process according to the invention. In all these, there is a drawing device rotating at a higher speed introduced in front of the device for collecting the thread, whether the latter is a bobbin or reel. The drawing device consists as a rule of a roller more or less encircled by the thread.

Fig. 1 is a diagrammatic side elevation of one form of the invention,

Fig. 2 is a view similar form of the invention,

Fig. 3 is a form of the invention similar to that shown in Fig. 1 with a reel being substituted for the spool shown in Fig. 1.

In the apparatus according to Figure l, l is a spinning device of the usual kind. The thread first travels from this around a guide rod 3, then through an acid treatment channelled member 4, over a drawing roller 5 and finally through a thread conductor 6 to the winding-on bobbin 1. As shown in the drawing, the thread encircles the to Fig. 1 of a modified roller 5 and then runs through the thread guide which is moved backwards and forwards in the direction of the double-headed arrow I, then on to the bobbin 1. The angle through which the thread is wound round the roller 5, the adhesion ratio, as well as the material of the roller 5, are so selected that as far as possible the thread does not slip upon the roller 5. This latter runs at a somewhat greater speed than that of the bobbin I, so that the thread is wound loosely on to the bobbin. Obviously, devices known in themselves could be incorporated which vary the speed of rotation to keep the thread speed at the bobbin constant, in spite of the increasing diameter of the mass of thread.

In Figure 2, a further drawing roller 8 is provided in front of the drawing roller 5, and a spout 9 is provided in place of the acid treatment channelled member 4 in front of the roller 5. The spout 9 conducts acidifying liquid on to the roller 5. A channelled member I is disposed below the roller in order to catch the acidifying liquid. The bobbin 1 and the thread conductor 6 are, in this case, arranged below the roller 5. In this arrangement, stretching again takes place between the rollers 8 and 5 to an extent determined by the speed of the rollers.

The arrangement in Figure 3 difiers from that of Figure 1 only in that the thread conductor 6 is again arranged below the drawing roller and that a reel ll serves to collect the thread. The reel is preferably placed low down, since it is then more easily handled owing to its greater dimensions.

What we claim is:-

1. A process for the production of artificial thread comprising forming the thread preliminarily by the cuprammonium stretch spinning process in a stream of precipitating liquid, then subjecting the thread to a considerable stretching, and winding the thread upon a rigid winding device under reduced tension.

2. A process for the production of artificial thread comprising forming the thread preliminarily by the cuprammonium stretch spinning process in a stream of precipitating liquid, then subjecting t e thread to a considerable stretching and app ying a setting solution to the thread while under tension, and winding the thread upon a rigid winding device under reduced tenslon.

3. A process for the production of artificial thread comprising forming the thread preliminarily by the copper oxide ammonia stretch spinning process in a stream of precipitating liquid,

then subjecting the thread to a considerable stretching, subsequently setting the thread only after substantial completion of the stretching, and winding the thread upon a winding device under reduced tension, said device being a rigid receiver upon which the thread is wound from the interior outwardly.

4. A process for the production of artificial thread from cellulosic solutions, comprising forming the thread by the stretch spinning process in a stream of precipitating liquid, then subiecting the thread to a further considerable stretching by drawing it without substantial slippage upon a drawing rollerrotating at a regulated speed, and thereafter collecting the thread upon a rigid receiver upon which the thread is wound from the interior outwardly, said receiver being rotated so as to have a slower peripheral speed than that of the drawing roller.

so 5. A process for the production of artificial eral speed of the drawing mller.

thread comprising extruding the filaments and subjecting them while plastic to a considerable stretching and thereafter windingthem upon a risid holder under reduced tension. 6. A process for the productionof artificial thread comprising extruding the filaments and subjecting them while plastic to a considerable stretching, applying a iixing solution to the illsments whileunder tension and thereafter wind- :18 them upon a rigid holder under reduced ten- 7. A process for the production of artificial thread comprising extruding the filaments and subjecting them while plastic to a considerable stretching by means of a drawing roller, and thereafter winding them upon a holder rotating at a lower peripheral speed than the periph- GOI'I'HARD BAURIEDEL. 

